Tunnel-shield.



1. C. MEEM..

` TUNNEL SHIELD. APPLICATION FILED SEPT.I8. 19H.

Patented Nov. 13, 1917'.

c, livrniuvn or BROOKLYN, NEWYORK, ASSIGNOR or oNE-HALET FREDERICKIL Y *d 1- vSpecification bf LetterslPetent. l

lJ'JJ-UNleien-SHIELD.

v'citizen 'o'f'gthe @United States; .'residing at Brooklyn, in' theippnty. of lnge angstate of New York, have"inventedcertainnew 1f and useful Improvements inTunneliShields,

Y ofwhichth'e followi Ang'k is a full, jclearzend exactspeciiication'. t. invention relates'vto ltunnel. shields,

such as are used for subterraneousandsubaqueous eXcavation, and mor'efespecially toy thosein dry subterrane'ou's; excavations where itymay not be"neces'sary to use compressed air,' butwhere 'the spaces round the tunnel .left by the advance of theftail of the shield f lli-@vetteietngtrunqmf-the Shield itself,

Y -end at the same'tiine t fprovide ineens whereby thetunnel; rings maybe prevented:

- Afrom settling;andfdistbrtinglw n thfslfeld l; enseignait/#lement etere V"constructed,' `tunnel shleldsjck'):nfs'iA `plates or segments; iorming'- tu ntfleayinglvsutli'ci'entey Space so fthatftlie shieldcanftbe moved fon-werd when "one tunnel sectionV has beenf'completed. It

l is desirable "to v'cOYI @theftunnel as far 1 @practicalwithiapf also A to `fill `vthe spiace'betwe i t eriintoY tortion of the ioih" within.l Verio'us Vmethods lhave beenemployed,Y such as inflatable bags placed between theuturnhielfrlng and Vthe shield,` yiibrousfL-inateri'als; Tand the like,'to prevent thefescapeot compressed air and the yconsequent influ`xof`water5'-but very little has been don'eitopreventgthe. settle-` ment caused'b `the failurek'to lill thespaces left by the shieldrtailin advancing. the solid formsfof shields heretofore employed difficulty has been encountered Vin Elling the space around the tunnel left by vthe shield when it is pushed forward. 'The present 4method most commonly employed is to entera pipe from lwithin and force liquid vconcrete or grout through Vthis pipe so as to vsurround and protect thetunnel tube. It is dueto the :thicknesso `'small thickness oit the kshield l tailf -"itselif,V 'which can be reducedto lVith :'segmental coveringy blocks, or both.` The shieldis advanced.

practicable, howev'jtoinsert thergioijit this manner as-the outen'inaterial' frequently Patented-,Nov- 4 eolla'pses beforevthegritleanibefplaced' or .i beforeit is suiliciently setto be of anyyalue.-

'The present invention f'f'itobject to Provide en mprQ-Y dA tunnel tube Y can be laid as each ltunn'elfsection is e recte'd,`y and also permitting the fen ab? functionv offla iil'lingfbetween vthe interi oftnehshieri nur the ex entr; efthenmee1- y y' ment/" or collapse, .1 the lar 'section llravingtheA usual forwar wat , n t "Bygrut'ng, even the spaces left bythenbemty tenute,

Thereby 'the tunnel tube spaces thus left will'be "const ruietion'ofshield' whereby a protectlvef4 covering around V theV vshieldf tof be pushed forward without-disp .turbing this :covering'and"leaving o solute liinimnml Y0f -Y'Ode' behind the 1sh'eltl.- the lSame time thisfcovering fperforinsthe the 'exterlprj Q their the ribs, een beilled immediately Letter the f a minimum]thickk ',nessby virtuejof 'theb'ridging strength of v [the ribs supporting-fin comparison2 wthfthe will be reduced to aminiinurn, andi-water can easily be kept out, or air, ifused, easilyA n prevented from tendency of the tunnel sections to distort owing `to a large and unfilled space leftby the shield tail at the sides and bottom between -A the outer edge of the tail and the tube.

escaping. `There' will be no` 1to0'` l so small that ,settlingv in the accompanying drawings is illustrated one embodiment ot the invention, wherein,

Figure lis a cross section of a tunnel shield embodying the invention taken on the line l-l of Fig. 2; and

Fig. 2 is a longitudinal section taken on the line 2 2 of Figt l.

The shield l is considered to be advancing to the lett in the direction of the arrow, Fig. 2, by power applied thereto such as by hydraulic jacks 2 or other suitable means. The forward or cutting end of the shield may be of any well known construction, and the shield may have a bulk-head according to common practice, or not, as desired. T his invention is however, especially concerned with the rear end of the shield, which instead ot' being otheavy plate metal practically fitting the outside et the tunnel rings 3, .is ot' thinner metal somewhat spaced therefrom, and provided with' spaced interior longitudinally extending ribs d which bear, or almost so, on the exterior of the tunnel tube segments. See Fig. l. Thereby, between the rear of the shield 1 and the exterior of the tunnel segments 3 and the successive ribs 4, are formed segmental spaces These segmental spaces 5 are to be iilfled with a illing as G, immediately after the tube segments are erected, and before the shield is advanced. See Fig. 2. The filling and covering material G may be gravel, orconc'rete poured therein vfrom within the shield, or

specially formed segmental blocks, or bricks. The ribs #i constitute supports for the relativelyzlight tubular tail l, and are normally slightly spaced'trom the tunnel rings 3, so

ythat the shield may bei directed up or down,

or laterally as desired. Also, the ribs will bear on the tunnel rings sutliciently to vprevent collapsing of the shield tail by' outside pressure, without interfering withthe advancing of the shield. The forward end vill of course be internally strengthened as shown so as to be seltl sustaining. The shield tail will carry the ribs 4 with it, without disturbing the iilling (i, and the relatively thin spacesv due to the thickness of the ribs and the thickness oi the shield tail will-be substantially illed by the surrounding` material without endangering adjacent buildings, even if the liquid grout above re- Copies ferr-ed to is notV employed. At the same time, the iilling G prevents inrush otl water, 55 or escape oi' air. l(onsequently, the advancing of the shield does not necessitate the moving` of an inliatable filling to the new position, nor does it leave large voids which have to be filled with grout after the shield ismoved in order to prevent thecompleted tunnel sections from sinking, as is the case with an ordinary thick or heavy tail shield. By this invention, shield excavations can be more quickly made owing to avoidance oi' 65 delays in back filling by previously used methods, and settling of the completed tunnel, and otsurrounding material and buildings is prevented.

Having thus described my invention, I declare that what I claim as new and desire to secure by Letters Patent, is

l. In combination, a tunnel wall, a shield spaced around the Jfront end portion of said wall and projecting beyond the same, means acting between said wall and shield for advancing the. shield, internal guides on the shield in the space between said wall and shield, said guides being spaced apart circuinferentially so as to' leave spaces between 80 them accessible underthe shield in front of the'wall, and filling material in said spaces.

y 2. In combination', a tunnel shield having a forwardv cutting end, longitudinal interior ribs on its rear end portion, a Vcompleted front end tunnel wall portion'. within said shield, said ribs constituting'guiding supports for the shield on ysaid completed wall portion, and illing material inV the spaces between said ribs.

3. ln combination :with a tubular tunnel,

a tubular tunnell shield'sliding exteriorly there-on comprising a tubev larger vthan the exterior diameter of the tunnel, internal longitudinal ribs on the shield tube adapted to guide and support the shield on the tunnel tube, and filling material'in ther spaces between said ribs' and within said shield.

In testimony whereo'tl ailix my signature, 100 in presence ot two witnesses.

JAMES c. MEEM.

Vitnesses:

JULIAN S. VOOSTER, K. G. Ln ARD.

of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

